【摘要】 提出了一种嵌套式双U形缺陷接地结构(DGS)来实现低通滤波器,可以获得良好的矩形特性.对嵌套式双U形DGS进行了精确的时域有限差分法数值分析,研究了其几何尺寸和单元个数变化对阻带特性的影响.在微带平面添加短截线,研究了短截线的长度变化对阻带特性的影响.研究结果显示,可以通过改变嵌套式双U形单元的几何尺寸来调节该结构的截止频率,也可以通过调节短截线的长度来改变该结构的截止频率,而通过多个嵌套式双U形单元的级联可以获得更深的阻带,这种关系能为嵌套式双U形DGS的分析和设计提供有力的指导.更多还原

【Abstract】 A novel nested double U-shaped defected ground structure(DGS) was proposed in this paper,which could be used to design the low-pass filter(LPF) with good rectangle characteristic.The precise transmission coefficient of nested double U-shaped DGS was obtained through finite-difference time-domain(FDTD) analysis.The influences of lattice dimensions,cells number,straight microstrip line on the characteristic of frequency were studied.A method about controlling the cut-off frequency by altering the length of straight microstrip line or the lattice dimensions was presented and discussed.And better stopbands could be obtained through coupling many nested double U-shaped DGS cells.This will provide a powerful tool for the analysis and design of LPF using nested double U-shaped DGS.更多还原